Long term changes in African savanna wildlife and land cover : pastoralists or policies

Homewood, K., Lambin, E. F., Coast, Ernestina ORCID: 0000-0002-8703-307X, Kariuki, A., Kikula, I., Kivelia, J., Said, M., Serneels, S. and Thompson, M. (2001) Long term changes in African savanna wildlife and land cover : pastoralists or policies. Proceedings of the National Academy of Sciences of the United States of America, 98 (22). pp. 12544-12549. ISSN 0027-8424

Preview

PDF Download (158kB) | Preview

Abstract

Declines in habitat and wildlife in semiarid African savannas are widely reported and commonly attributed to agropastoral population growth, livestock impacts, and subsistence cultivation. However, extreme annual and shorter-term variability of rainfall, primary production, vegetation, and populations of grazers make directional trends and causal chains hard to establish in these ecosystems. Here two decades of changes in land cover and wildebeest in the Serengeti-Mara region of East Africa are analyzed in terms of potential drivers (rainfall, human and livestock population growth, socio-economic trends, land tenure, agricultural policies, and markets). The natural experiment research design controls for confounding variables, and our conceptual model and statistical approach integrate natural and social sciences data. The Kenyan part of the ecosystem shows rapid land-cover change and drastic decline for a wide range of wildlife species, but these changes are absent on the Tanzanian side. Temporal climate trends, human population density and growth rates, uptake of small-holder agriculture, and livestock population trends do not differ between the Kenyan and Tanzanian parts of the ecosystem and cannot account for observed changes. Differences in private versus stateycommunal land tenure, agricultural policy, and market conditions suggest, and spatial correlations confirm, that the major changes in land cover and dominant grazer species numbers are driven primarily by private landowners responding to market opportunities for mechanized agriculture, less by agropastoral population growth, cattle numbers, or small-holder land use.

Item Type:	Article
Official URL:	http://www.pnas.org
Additional Information:	Published 2001 © National Academy of Sciences. LSE has developed LSE Research Online so that users may access research output of the School. Copyright © and Moral Rights for the papers on this site are retained by the individual authors and/or other copyright owners. Users may download and/or print one copy of any article(s) in LSE Research Online to facilitate their private study or for non-commercial research. You may not engage in further distribution of the material or use it for any profit-making activities or any commercial gain. You may freely distribute the URL (http://eprints.lse.ac.uk) of the LSE Research Online website. Article does not contain tables or figures; a peristent link to the article, as published, is available at http://dx.doi.org/10.1073/pnas.221053998
Divisions:	LSE
Subjects:	G Geography. Anthropology. Recreation > GF Human ecology. Anthropogeography G Geography. Anthropology. Recreation > GN Anthropology
Date Deposited:	21 Jun 2006
Last Modified:	07 Oct 2024 02:33
URI:	http://eprints.lse.ac.uk/id/eprint/269

Actions (login required)

View Item